Electronic payments may be performed in a variety of ways. A payment terminal may process payment transactions, and may interact with payment devices such as a payment card having a magnetic strip that is swiped in a magnetic reader of the payment terminal, a payment device having a Europay/Mastercard/Visa (EMV) chip that is dipped into corresponding EMV slot of the payment terminal, and near field communication (NFC) enabled devices such as a smartphone or EMV card that is tapped at the payment terminal and transmits payment information over a secure wireless connection. The payment terminal may receive payment information from the payment device as well information about a transaction, and may communicate this information to a payment system for processing of the transaction.
As a result of its central role in the transaction processing system, the payment terminal is a prime target for third party attackers attempting to access payment information, process fraudulent transactions, and otherwise engage in fraudulent activities or theft. In many cases, the attackers attempt to physically access components of the payment terminal, such as one or more communication lines carrying data or a processor that communicates and processes payment information. Attackers may attempt to eavesdrop on signals (e.g., a passive attack) or to modify or spoof payment processing communications (e.g., an active attack) by injecting malicious signals into the payment terminal.
A payment terminal may attempt to identify fraudulent transactions and tamper attempts. However, as attackers become more sophisticated, measures such as tamper switches or tamper meshes may be bypassed, or attacks may be performed without gaining physical access to any components of the payment terminal. For example, some attackers may create counterfeit or modified payment cards (e.g., EMV cards), or may construct tamper devices that intercept, forward, or modify signals transmitted between a payment terminal and a payment device. Moreover, a payment terminal may also lack information about other payment transactions that are occurring, and thus, other attempts to engage in fraudulent transactions or to tamper with a payment reader.